Refrigerating system



Dec. 20, 1949 w. A. RAY

REFRIGERATING SYSTEM Filed May 29, 1944 FINVENTOW Dev/um (ImndenwrPatented Dec. 20, 1949 UNITED REFRIGERATING SYSTEM William A. Ray,Glendale, CallL, assignor to General Controls 00., a corporationApplication May 29, 1944, Serial No. 537,774

7 Claims. (Cl. 62-427) This invention relates to refrigeration, andespecially to a system in which heat is absorbed by vaporization of arefrigerant, such as Freon.

Such systems operate upon a cycle that is now well known. The liquidrefrigerant is conducted to an evaporator or expansion coil, where theliquid vaporizes and absorbs heat. Then the gaseous refrigerant iscompressed and recondensed into liquid form.

For passing the liquid into the expansion space, use is made of a valvethat automatically responds to one or more conditions of the system,such as the degree of superheat attained by the vaporized refrigerantadjacent the outlet end of the coil.

In order to improve the efliciency of the refrigeration, it is now knownto provide a plu rality of evaporating coils in parallel arrangement,all of the coils having inlets controlled by a common inlet valve.

In order for the heat load to be distributed uniformly on theevaporator, ensuring that the evaporator be operated at maximumefllciency,

it is necessary that the refrigerant be distributed substantiallyuniformly among these coils or units. It is accordingly an importantobject of the present invention to provide a multi-circuit evaporatorsystem, in which it is ensured that the refrigerant admitted to theunits of the evaporator is uniformly distributed.

As a means of distributing refrigerant to such a multi-circuitevaporator, an expansion valve having a main valve controlled port iscommonly used, there being a plurality of outlets fed from such port fordistributing the refrigerant to the evaporator units. The meteringaction of such a valve with respect to the evaporator units isunsatisfactory, resulting in unequal rate of flow to the differentunits; and, hence, the system operates at reduced efficiency. Thisoccurs because the pressure drop across the valve takes place in twosteps. It is thus another object of this invention to provide anexpansion valve for use with a multi-circuit evaporator, arranged sothat the entire pressure drop across the valve takes place in but asingle step.

It is another object of this invention to pro vide an expansion valvehaving a plurality of discharge openings simultaneously controlled by asingle valve member.

It is another object of this invention to provide such a valve whereinthe valve member controlling the ports is electrically controlled.

It is another object of this invention to provide a valve incorporatingthe foregoing features which has a minimum of moving parts, and is ofsimple and rugged design.

It is another object of this invention to provide an expansion valvehaving a plurality of discharge ports wherein the valve closure isarranged quickly to open and close, without the possibility of theclosure remaining in a partly opened position. In this way any wiredrawing of the refrigerant, as well as possibility of cutting of thevalve seats, is prevented, and equal discharge of the refrigerant by theseveral discharge ports is assured.

This invention possesses many other advantages, and. has other objectswhich may be made more readily apparent from a consideration of oneembodiment of the invention. For this purpose there is shown a form indrawing accompanying and forming part of the present; specification.This form will now be described in detail, illustrating the generalprinciples of the invention; but it is to be understood that thisdetailed description is not to be taken in a limiting sense, since thescope of this invention is best defined by the appended claims.

Referring to the drawing:

Figure 1 'is a diagrammatic showing of a refrigerating systemincorporating the invention;

Fig. 2 is a vertical section on an enlarged scale,

taken on a plane passing through the center line of the distributorvalve; and

Fig. 3 is a cross section taken substantially on plane 3-3 of Fig. 2.

Referring to Fig. 1 of the drawing, a multi-circuit refrigerating systemis shown. This system includes a plurality of evaporators, four beingshown in the present instance, and marked with reference characters I,2, 3, and 4, which may each be in the form of convoluted tubing andwhich may be enclosed in the space to be cooled. Liquid refrigerant ispassed to the evaporators l, 2, 3, and 4 from the condenser 5 by meansof a valve 6, which is arranged to be controlled in accordance withdesired conditions produced by the refrigerant. For this purpose valve 6may be electrically actuated and controlled by an automatic controldevice 1, which is arranged to switch valve 6 into or out of an electriccircuit, for example, in accordance with changes in temperature producedby the evaporators, or the degree of superheat present in the vaporizedrefrigerant adjacent the outlet of the vaporizer. The outlets of theevaporators l, 2, 3, and 4 are connected to a common conduit 8 whichleads to the intake of a compressor 9, the discharge ill of thecompressor being connected to the condenser 5. The

' liquid supplied to each unit, the valve 6 manner in which theoperation of the compressor is controlled forms no part of the presentinvention.

The cycle of refrigeration consists of theadmission of liquidrefrigerant through valve 6 slmultaneouslyinto the evaporators I, 2, 3,and 4,

'where the pressure and temperature conditions and thence to compressor9, where it is compressed. The compressed gaseous refrigerant is thencooled by the aid of condenser 5 so as to be reconverted to a liquid,and the cycle is then repeated.

In multi-circuit evaporators of this type, it is important that theevaporators I, 2, 3, and 4 be supplied simultaneously with equal amountsof refrigerant to assure operation of the system at maximum efllciency,as well LS to utilize effectively the entire surface of the evaporators.Thus, a single valve, as 6, having a plurality of discharge openings oroutlets, H, l2, l3, and I4 connected respectively to evaporator units I,2, 3, and 4, is provided, the discharge from these openings beingvcontrolled by a valve closure member l'l. Furthermore, to ensureaccurate metering of the 1S arranged so that the entire pressuredropacross the valve to each unit takes place in one step.

Referring to Figs. 2 and 3, valve 6 comprises a body l8 having avertical axis l9 and a plurality of horizontally extending bossesdisposed in spaced angular relationship about axis l9, each boss havinga discharge opening or outlet, ll, l2, l3, or [4, formed therein. Thus,as shown, there are four such bosses and outlets for a four unitevaporator; but, obviously, the number of bosses and outlets could beincreased or decreased to adapt the valve for use with an evaporatorhaving a different number of circuits or units. Body l8 also has anaxial boss 2| for accommodating the inlet connection 22 from thecondenser, as well as an axial port 23 which forms an inlet port leadingupwardly therefrom into a space 24 formed by a cap 25 secured ingas-tight relation on top of body l8. A plurality of metering orificesor ports 3 I, 32, 33, and 34 lead downwardly to connect space 24respectively with discharge openings or outlets ll, I2, l3, and I4.Oriflces or ports 3|, 32, 33, and 34 are angularly spaced about axis l9,and are each provided with a tubular extension 3l-a, 32-41, 33-11, and34-a projecting slightly above the top of valve body la.

The tops of the extensions 3I-a,.32 -a, 33a,

and 34-a lie in a common plane and form valve seats whereby the closuremember H, which has a plane lower surface, is adapted to close theorifices by resting on the ends of the extensions.

The space 24, surrounding closure I! in the valve body, is filled withliquid refrigerant at all times; accordingly, when the valve closuremember I! is lifted, only liquid refrigerant can enter the ports 3|, 32,33, and 34. Since these ports have cross sectional areas substantiallyless then the cross sectional areas of the corresponding outlets H, l2,l3, and I4, no expansion occurs until the refrigerant reaches theseoutlets. In other words, the metering occurs always in a wholly liq= uidstate of the refrigerant. Thereby, uniform quantities of the refrigerantpass into each outlet l2, l3, and M.

Means are provided for operating valve 6 elec trically. Thus the core 23of an el is secured to body I8 as by a flanged inverted cup 21, theflange 23 of which is clamped to body II by a flange 29. A suitablegasket may be interposed between flange 28 and body l3 to pre-' ventleakage. The upper end of core 23 has a reduced portion 35 which extendsthrough a suitable opening 36 in the top of cap 25, being rolled over,as indicatedat 31, to secure the core and the cap in assembledrelationship. Core 26 and cap 25 together define an annular space for accommodating a winding 40. The leads 4| and 42, extending through anopening (not shown) in cap 25, serve to connnect the winding to apparatus for appropriately energizing the winding.

To ensure closure member I! returning to closed position uponde-energization of the magnet assembly 26, 40, a light compressionspring 43 is accommodated in recess 44 formed in the lower face of core26 and recess 45 formed in closure member II. This spring 43 also actsto prevent any undesired unseating of closure I'I incident to vibrationor other causes. To guard against any dash pot" action or restraint onthe movement of closure I! by fluid present in space 24, openings ll-amay be provided in the closure member. A center opening 46 in closure llassists in ensuring free flow of the liquid refrigerant to space 24. Theinner circumference of the inverted cup 21 serves to guide the closurell axially, suitable clearance being provided between this surface andthe periphery of the closure member to ensure free movement of theclosure.

An important feature of this valve is that the pressure drop between theinlet 22 and each of the outlets H, l2, l3, or I4 occurs in a singlestep for each outlet. Since the metering orifices or ports and all otherparts are identical for each outlet, only one outlet need be discussed.Thus, considering outlet l2, for example, it will be clear that withmember ll unseated suiliciently freely to admit liquid refrigerant toorifice 32, the only place where the cross section of this passagewayincreases, and where pressure drop and vaporization of the refrigerantcan occur, is at the entry of the orifice into discharge outlet l2.Thus, the metering, orifice is only called upon to handle liquid whichfurthermore is passed by gravity into the orifice. The subsequentpassages are relatively large; and, whether the refrigerant passestherethrough as entirely vapor, or partly vapor and partly liquid, is ofno consequence, since no further metering is required.

The inventor claims:

1. In a refrigerating system having a plurality of evaporators arrangedto be supplied from a common source of liquid refrigerant underpressure, said refrigerant being of a type which flashes into gas upon asuitable reduction in said pressure: a valve structure having an inletconnected to said source, as well as a plurality of outlets respectivelyconnected to said evaporators, means forming an enclosed chamber inconstant communication with the inlet, said valve also having aplurality of ports connecting said chamber to the respective outlets,said ports each having a cross section substantially less in area thanthat of the corresponding outlet, and having a combined areasubstantially less than the area of said inlet, and a closure memberwithin said chamber simultaneously controlling each of said portsindividually.

2. In a refrigerating system having a plurality of evaporators arrangedto be supplied from a common source of liquid refrigerant underpressure, said refrigerant being or a type which flashes into gas upon asuitable reduction in said pressure: a valve body having an inlet; meansforming an enclosed chamber in constant communication with the inlet,said body having a number of outlets connected to the evaporators, aswell as ports extending from the chamber respectively to the outlets,each of said ports serving as a direct communication between therespective outlet and the chamber, and having a cross section area lessthan that of the corresponding outlet, the combined areas of said portsbeing substantially less than the area of said inlet; a closure memberin the chamber for covering all of the ports, and

, upon being raised, exposing the full cross section of the ports to thechamber; and means for raising said closure member.

3. In a distributor valve for liquid refrigerant under pressure, saidrefrigerant being of a type which flashes into gas upon a suitablereduction in said pressure: a valve body having an inlet; means disposedover the body and sealed thereon, forming a chamber; said inletextending through the body and being in constant communication with thechamber; said body having a number of outlets, as well as portsextending from the chamber respectively to the outlets, each of saidports serving as a direct communication between the respective outletand the chamber, and having a cross section area less than that of thecorresponding outlet, the combined areas of said ports beingsubstantially less than the area of said inlet; a closure member madefrom magnetic material and in said chamber, and having a surface forcovering all of the ports, and upon being raised, exposing the fullcross section of the ports to the chamber; and an electromagnetoperating on said closure member to raise it from the ports.

4. In a distributor valve for liquid refrigerant under pressure, saidrefrigerant being of such character as to flash into gas upon a suitablereduction in said pressure: means forming a valve body having a chamberin constant communication with an inlet, and a plurality of separateoutlets, said body having a plurality of ports leading from said chamberto said outlets respectively, said ports having cross sectional areassubstantially less than those 01 the corresponding outlets, the combinedareas of said ports being substantially less than the effective area ofsaid inlet; and means within said chamber for controlling the passage ofrefrigerant through said ports.

5. In a distributor valve for liquid refrigerant under pressure, saidrefrigerant being of such character as to flash into gas upon a suitablereduction in said pressure: means forming a valve body having a chamberin constant communication with an inlet, and a, plurality of separateoutlets, said body having a plurality of ports leading from said chamberto said outlets respectively. said ports having cross sectional areassubstantially less than those of the corresponding outlets, the combinedareas of said ports being substantially less than the effective area ofsaid inlet; and a closure member within said chamber for controlling thepassage of refrigerant through said ports.

6. In a distributor valve for liquid refrigerant under pressure, saidrefrigerant being of such character as to flash into gas upon a suitablereduction in said pressure: means forming a valve body having a chamberwith an inlet, and a plurality of separate outlets, said body having aplurality of ports leading from said chamber to said outletsrespectively, said ports having cross sectional areas substantially lessthan those of the correponding outlets, the combined areas of said portsbeing substantially less than the elfective area of said inlet; aclosure member having a face for simultaneously closing all of saidports; means forming a surface spaced from said member when in portclosing position and serving to limit movement of ,said closure memberaway from port closing position; and means for operating said closuremember between port opening and port closing position.

'7. In a distributor valve for liquid refrigerant under pressure, saidrefrigerant being of the character which flashes into gas upon asuitable reduction in said pressure: means forming a valve body having achamber with an inlet and a pinrality of separate outlets, said bodyhaving a plurality of ports leading from said chamber to said outletsrespectively, each of said outlets having a cross sectional area largerthan that of the corresponding port; means ensuring a supply of liquidrefrigerant for said ports; means forming a valve seat for each of saidports; an electromagnet having a face spaced from said seats, a

magnetic closure member interposed between,

said face and said seats for free movement therebetween and urged toseat and close said ports; said member when the electro-magnet is:energized being moved to engage said face and expose the full crosssection of said ports, and when the magnet is deenergized moving toengage said seats and closing said ports.

WILLIAM A. RAY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

